【摘 要】
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The authors have designed and fabricated a new apparatus for rapid heating and quenching of Powder-in-Tube (PIT) Nb/Al precursor.Short superconducting Nb3Al samples are obtained after heat treatment a
【机 构】
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School of Materials & Metallurgy, Northeastern University, Shenyang 110819, China
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The authors have designed and fabricated a new apparatus for rapid heating and quenching of Powder-in-Tube (PIT) Nb/Al precursor.Short superconducting Nb3Al samples are obtained after heat treatment at 800 ℃C for 10h.Superconducting properties are studied through four probe method in cryocooler.A transport critical current density without Cu of 325 A/mm2 is obtained at 11 K, self field.The critical temperature is about 17.8 K.Magnetic hysteresis loops at 10K and 12K are obtained.Photographs from SEM show that Nb3Al phase is well formed.However, small amount of Nb and Nb2Al exists in the wire.Further optimization is still needed to improve the current transport ability and mechanical properties of the samples.
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